Clinical significance of Midkine expression in pancreatic carcinoma

Objective To investigate the clinical significance of Midkine (MK) expression in pancreatic carcinoma (PC) and its relationship with proliferation of tumor cells. Methods Immunohistochemical staining method (SP method) was used to study Midkine and Ki67 expression in pancreatic carcinoma samples of 49 cases, chronic pancreatitis (CP) samples of 13 cases and normal pancreatic tissues of 15 cases. Results The expression of MK and Ki67 was high in pancreatic carcinoma tissues, the positive rate being 77.1% (35/49) and 81.6% (40/49), respectively. The expression of MK and Ki67 was significantly correlated with histological grades, clinical stages and lymph node metastasis (P 0.05). The expression rate of Ki67 was much higher in pancreatic carcinoma than in chronic pancreatitis (3/13, P 0.01) and normal pancreatic tissues (0/15, P 0.01). The expression of MK was not detected in normal pancreatic and chronic pancreatitis tissues. The expression level of MK had a positive relationship with Ki67 in pancreatic carcinoma(r = 0.4, P 0.05). Conclusions Determination of MK protein may be used as a useful marker in the diagnosis of pancreatic carcinoma and differential diagnosis between PC and CP. Overexpression of MK in pancreatic cancer may be closely correlated with the development and progression of carcinoma and cell proliferation. MK might be considered as a specific target of gene therapy and drug therapy of pancreatic carcinoma. Specific blocking of MK expression may play a role in inhibiting proliferation of pancreatic cancer cells.